/**
 * Copyright (c) 2006-2008, Alexander Potochkin
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/or other materials provided
 *     with the distribution.
 *   * Neither the name of the JXLayer project nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.jdesktop.jxlayer.plaf.item;

/**
 * This interface represents an abstract type which usually provides
 * some kind of {@code JXLayer}'s decoration.
 * <p/>
 * It defines {@code isEnabled()} method and 3 methods to provide
 * change notification via {@link LayerItemListener}.
 *
 * @see org.jdesktop.jxlayer.plaf.LayerUI
 * @see org.jdesktop.jxlayer.plaf.effect.LayerEffect
 */
public interface LayerItem {
    /**
     * Indicates if this {@code LayerItem} is in active state.
     *
     * @return {@code true} if this {@code LayerItem} is in active state
     */
    public boolean isEnabled();

    /**
     * Adds a {@code LayerItemListener} to the layer item.
     *
     * @param l the listener to add 
     */
    public void addLayerItemListener(LayerItemListener l);

    /**
     * Returns an array of all the {@link LayerItemListener}s
     * registered on this {@code LayerItem}.

     * @return all of this item's {@code LayerItemListener}s 
     * or an empty array if no item listeners are currently registered
     */
    public LayerItemListener[] getLayerItemListeners();

    /**
     * Removes a {@link LayerItemListener} from this {@code LayerItem}.
     *
     * @param l the listener to remove
     */
    public void removeLayerItemListener(LayerItemListener l);
}
